body {
            background-color: #0f172a; /* Slate 900 */
            color: white;
            margin: 0;
            display: flex;
            justify-content: center;
            align-items: center;
            min-height: 100vh;
        }

        #rtb-game-wrapper {
            font-family: 'Press Start 2P', monospace;
            display: flex;
            flex-direction: column;
            align-items: center;
            width: 100%;
            max-width: 600px;
            margin: 0 auto;
            background-color: #111827;
            padding: 20px;
            border-radius: 12px;
            box-shadow: 0 4px 6px rgba(0,0,0,0.3);
            border: 2px solid #374151;
            min-height: 650px;
            position: relative;
        }

        /* --- Stats Bar --- */
        .stats-bar {
            display: flex;
            justify-content: space-around;
            width: 100%;
            max-width: 400px;
            font-size: 0.65rem;
            color: #fbbf24;
            margin-bottom: 15px;
            background: #1f2937;
            padding: 10px;
            border-radius: 8px;
            border: 1px solid #374151;
            text-transform: uppercase;
        }

        .stat-val { color: white; margin-left: 5px; }

        /* --- Cards --- */
        .card-container {
            display: flex;
            justify-content: center;
            gap: 15px;
            margin: 20px 0;
            height: 140px;
        }

        .card-slot {
            width: 90px;
            height: 130px;
            border: 2px dashed #4b5563;
            border-radius: 8px;
            display: flex;
            justify-content: center;
            align-items: center;
            font-size: 3rem;
            background-color: #1f2937;
            transition: all 0.3s ease;
            position: relative;
        }

        .card-slot.active-slot {
            border-color: #facc15;
            box-shadow: 0 0 10px rgba(250, 204, 21, 0.3);
        }

        .card-slot.revealed {
            border-style: solid;
            background-color: white;
        }

        .card-red { color: #ef4444; }
        .card-black { color: #1f2937; }

        /* --- UI Elements --- */
        .game-msg {
            height: 60px;
            text-align: center;
            color: #fbbf24;
            line-height: 1.5;
            margin-bottom: 20px;
            font-size: 0.8rem;
        }

        .btn-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 15px;
            width: 100%;
            max-width: 400px;
        }

        .rtb-btn {
            background-color: #3b82f6;
            color: white;
            padding: 15px;
            border: 4px solid #1d4ed8;
            border-radius: 8px;
            font-family: inherit;
            font-size: 0.7rem;
            cursor: pointer;
            text-transform: uppercase;
            transition: transform 0.1s, background-color 0.2s;
        }

        .rtb-btn:hover:not(:disabled) {
            transform: scale(1.02);
            background-color: #2563eb;
        }

        .rtb-btn:active:not(:disabled) {
            transform: scale(0.98);
        }

        .rtb-btn:disabled {
            opacity: 0.5;
            cursor: not-allowed;
            border-color: #4b5563;
            background-color: #374151;
        }

        .col-span-2 {
            grid-column: span 2;
        }

        /* Deck Info Footer */
        .footer-bar {
            display: flex;
            justify-content: space-between;
            width: 100%;
            font-size: 0.6rem;
            color: #9ca3af;
            margin-top: auto;
            padding-top: 20px;
            border-top: 1px solid #374151;
        }

        /* Animations */
        @keyframes shake {
            0%, 100% { transform: translateX(0); }
            25% { transform: translateX(-5px); }
            75% { transform: translateX(5px); }
        }

        .shake { animation: shake 0.3s ease-in-out; }
        
        .win-glow {
            animation: glow 1s infinite alternate;
        }
        
        @keyframes glow {
            from { box-shadow: 0 0 10px #22c55e; border-color: #22c55e; }
            to { box-shadow: 0 0 25px #22c55e; border-color: #4ade80; }
        }